Background Porous Materials can be used as not only physical filtration, but also as heat exchanger. I'm intended to test the performance of heat-exchanging wall of different materials (foam, wood and concrete) with different sizes of holes. My experiments are based on Salmaan and Jonathan' s result, which proves that a water circuit guarantee direct thermal contact and prevent radiant discomfort.
Illustration 1: Building envelope with porous material optimized to exchange heat to the incoming air with minimal conduction losses. 
Does the size of panels impact the efficiency of heat exchange? (diameter=1/8, 1/16, 1/32 inch)
The smaller the size is, the fewer the energy is lost, in the meantime, larger size have a larger capacity on exchanging heat.
1 Water circuit- Rhino- 3D printer
2 Foam/Wooden wall - AutoCAD - CNC
3 Concrete Wall: Mix water and lime powder, pour the mixture into themold made by 3D printer.
A written algorithm will control the temperature and flow rate of water with Arduino.
Sample of different sizes panels
Top view Interior------|-----------Exterior
Sources：  Salmaan Craigab, Jonathan Grinham, Breathing walls: The design of porous materials for heat exchange and decentralized ventilation, Harvard University